
body{
    background-size: cover;
    background-image: url(../img/2.jpg);
}

.container{
    margin-top: 15rem;

}
.card{
    background-image: url(../img/4.gif);
    background-size: cover;
}

/* 登录 */
.card-header{
    text-align: center;
    font-weight: bold;
}
/* 登录卡片 */
.form-group{
    width: 500px;
    font-weight: bold;
}

.btn-primary{
    margin-left: 7rem;
}





